Reaction mass of disodium hexatitanium tridecaoxide and disodium trititanium heptaoxide

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2010-03-30 to 2010-03-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP guideline study reliable without restrictions

Justification for type of information:

Disodium titanate substance (EC 234-802-9) has the molecular formula Na2TiO3 and its composition is expressed as (Na2O)x(TiO2), where x is ranging from 0.1 to 6 according to the SIP. This substance, Reaction mass of Disodium Hexatitanate and Sodium Metatitanate, has a value of x = 0.21, calculated from XRF results, has been identified as a mixture of two specific types of disodium titanate and is therefore within the scope of the disodium titanate SIP.
It is assessed therefore that disodium titanate is an acceptable read-across substance for Reaction mass of Disodium Hexatitanate and Sodium Metatitanate

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: OECD Guideline for Testing of Chemicals 437: Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants, September, 2009

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: INVITTOX (UK) protocol no. 98 “The Bovine Corneal Opacity and Permeability Assay”, February 1994

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: Bovine Corneal Opacity and Permeability (BCOP) Assay, SOP of Microbiological Associates Ltd., UK, Procedure Details, April 1997

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2009-03-30

Test material

Test material information

Constituent 1

Reference substance name:

Disodium titanate

EC Number:

234-802-9

EC Name:

Disodium titanate

Cas Number:

12034-34-3

Molecular formula:

Na2TiO3

IUPAC Name:

disodium titanate

Details on test material:

- Name of test material (as cited in study report): Disodium titanate
- Physical state: light yellow powder
- Storage condition of test material: At room temperature, in tightly closed container

No further information on the test material was stated.

Test animals / tissue source

Details on test animals or tissues and environmental conditions:

Not applicable - Since this is a in vitro study there is no information on test animals.

Test system

Vehicle:

physiological saline

Remarks:

0.9% (w/v) NaCl in deionised water

Amount / concentration applied:

Prior to the application of 0.75 mL the test item was suspended in saline (20% (w/v))

Duration of treatment / exposure:

Opacity measurement: incubation time: 240 min (+/- 5min)
Permeability of the corneae: 90 min

Observation period (in vivo):

not applicable

Number of animals or in vitro replicates:

not applicable

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): After the test item was rinsed off from the application side by changing cMEM three times.
- Time after start of exposure: 240 min (+/- 5 min)

SCORING SYSTEM:
The following formula was used to determine the in vitro score of the negative control:

In vitro Score = opacity value + (15 x OD490 value)

The following formula was used to determine the in vitro score of the positive control and the test item:

In vitro Score = (opacity value – opacity value mean negative control) + (15 x corrected OD490 value)

The in vitro score was calculated for each individual treatment and positive control cornea. The mean in vitro score value of each treated group was calculated from the individual in vitro score values.

TOOL USED TO ASSESS SCORE: fluorescein

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Run / experiment:

See details on "Details on Study Design" section

Value:

ca. -0.26

Vehicle controls validity:

valid

Remarks:

Vehicle: physiological saline 0.9%(w/v) NaCl in deionised water. Prior to application of 0.75mL, the test item was suspended in saline (20%(w/v))

Negative controls validity:

valid

Remarks:

Negative control: 0.9% NaCl solution. Neither an increase of opacity not permeability of the cornea could be observed. The mean in vitro score was calculated as 1.84

Positive controls validity:

valid

Remarks:

Positive control: 10%(w/v) Benzalconium chloride. Clear opacity and distinctive permeability of the cornea showed. The mean in vitro score was calculated as 155.94

Remarks on result:

no indication of irritation

Remarks:

The calculated mean in vitro score was -0.26. Therefore, non eye irritant.

Other effects / acceptance of results:

The test item Disodium titanate did not cause any opacity or permeability of the corneae compared with the results of the negative control. The calculated mean in vitro score was – 0.26 and therefore, the test item was classified as non eye irritant.

Any other information on results incl. tables

Results

Results after 240 Minutes Incubation Time

Test Group	Opacity value = Difference (t240-t0) of Opacity^*		Permeability at 490 nm (OD490)^*		In vitro Score	Mean in vitro Score	Proposed in vitro Irritation Scale
		Mean		Mean
Negative Control	1	1.00	0.059	0.056	1.89	1.84	Non eye irritant
	2		0.054		2.81
	0		0.054		0.81
Positive Control	153.00*		0.733*		164.00	155.94	Severe eye irritant
	160.00*		0.322*		164.84
	134.00*		0.332*		138.99
Disodium titanate	- 1.00*		- 0.008*		- 1.12	- 0.26	Non eye irritant
	- 1.00*		- 0.002*		- 1.03
	1.00*		0.024*		1.37

*corrected values

Historical Data

	Positive Control	Negative Control
Mean	137.19	2.22
Standard Deviation	34.87	0.47

Values of 36 studies with solid test items performed in 2008 and 2009

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In conclusion, it can be stated that in this study and under the experimental conditions reported, the test item Disodium titanate is not considered to be an eye irritant.

Executive summary:

The test item Disodium titanate did not cause any opacity or permeability of the corneae compared with the results of the negative control.

The calculated mean in vitro score was – 0.26 and therefore, the test item was classified as non eye irritant.